Definitely robust! I have two wild sons (3 and 6 years old). They run around with the JBL all the time and have thrown it on the floor a few times.

In my experience, the part is very robust. I have dropped it on the gravel floor, in the water and in the sand many times. Only the woofers on the sides could be damaged, but only if the speaker falls onto something sharp. Nothing happens to them when the floor is flat.